1. Technical Field
The present invention relates to a waist protection member for protection of a femur and more particularly, to a waist protection member suitable for the prevention of femur injury and fracture upon falling of elder persons with their bones weakened due to osteoporosis.
2. Background Art
Protection members have been conventionally provided for the protection of specific areas of human bodies from impact associated with falls or collisions. In general, the protection members of this type employ, as an impact absorber, various types of foamed resin materials, nonwoven fabrics or fluids such as air, and are adapted for attachment to specific areas ofthe human body. Protection members of various specifications have been proposed so as to conform to contours of protected human body areas such as the arm, breast and the like.
Upon impact to a lower body part due to a fall or the like, a great impact force is applied to a greater trochanter 1a of a femur 1 shown in FIG. 27. Therefore, in the case of falls of the elderly whose bones are weakened due to osteoporosis, they often sustain injury or fracture of a portion of the femur 1 and particularly of a cervical part 1b thereof Currently, such injuries or fractures of the elderly have become a social problem. Thus, various efforts have been paid to the protection of various human body areas and particularly, of the greater trochanter and its peripheral area (a waist area or a hip area).
For example, as shown in FIGS. 28A and 28B, U.S. Pat. No. 4,573,216 discloses a protection member 3 for the protection of the waist area including the greater trochanter 1a. This protection member 3 is substantially of an elongate ellipse shape. The device has a double-layer structure which includes an inner layer 3a formed of a partially cross-linked silicone rubber and placed against a surface of a human body 4, and an outer layer 3b formed of a cross-linked silicone rubber. This protection member 3 has a bell-shaped cross section wherein the thickness is the greatest at a portion corresponding to the greater trochanter 1a and gradually decreases toward a periphery ofthe member. The inner layer 3a has a thickness of not more than 40 mm. A total thickness combining those of the inner layer 3a and the outer layer 3b is in the range of 20 to 50 mm.
As shown in FIG. 29, another protection member 6 is disclosed in U.S. Pat. No. 5,497,511. The device is formed of a resin material and placed within a pocket 5a of pants 5.
Further, as shown in FIGS. 30A and 30B, in Japanese patent application No. 7-62520 (Japanese laid-open application No. 8-209409), the present applicants have previously proposed a protection member 8 adapted for placement in pockets 7a, 7a positioned at lateral-sides of pants 7 and composed of a gel-like substance.
As shown in FIGS. 31A and 31B, another protection member 12 is disclosed in U.S. Pat. No. 5,034,998. This protection member takes the form of a skirt, comprising a polymer sheet base 9 formed of an air-impermeable polymer material, such as polyethylene, polyvinyl chloride, polypropylene or the like. The protection member also has a bubble layer 10 which includes a plurality of recesses circular in section and is adhesively or ultra-sonically bonded to the sheet base 9 for defining a plurality of fluid filled chambers 11. The chambers 11 are filled with fluid such as a gas like air or a liquid like water. In FIG. 31 A, a reference numeral 13 denotes a tensile belt strip with a fastener element for attachment of the member to a lower body part.
However, the protection member 3 of above mentioned U.S. Pat. No. 4,573,216 shown in FIGS. 28A and 28B is designed such that one piece of protection member 3 serves to protect the greater trochanter 1a and its peripheral area, and hence, has a great surface area (contact area) in abutment against or in contact with the human body surface 4. Furthermore, as mentioned above, the protection member 3 has a thickness as great as 20 to 50 mm. Therefore, the protection member 3 is incapable of deforming in a manner to fully follow the movement of the human body 4 at the greater trochanter 1a and its peripheral area. Consequently, when worn, this protection member 3 restricts the movement of the human body 4, causing discomfort to a wearer. Furthermore, the protection member 3 has a relatively great weight, resulting in poor wear comfort.
The protection member 6 of above-mentioned U.S. Pat. No. 5,497,511 shown in the FIG. 29, also has a great contact area with the human body and a relatively high hardness, resulting in poor conformability to the movement of the human body and poor wear comfort.
Since the protection member 8 of FIGS. 30A and 30B proposed by the present applicants is formed of a gel-like substance, the protection member 8 is more flexible than the protection members 3, 6 shown in FIGS. 28A, 28B and 29. However, this protection member 8 also has great contact area with the human body, resulting in insufficient conformability to the movement of the human body.
The protection member 12 of U.S. Pat. No. 5,034,998 shown in FIGS. 31A and 31B has an arrangement wherein the plural fluid chambers 11 establish respective point contacts with the human body so as to define a small contact area with the human body. However, when this protection member 12 is worn, the one piece of polymer sheet base 9 covers all the fore, back and lateral areas of the waist, thus restricting the movement of the wearer. In addition, a fear exists that any of the fluid chambers 11 may rupture to cause the gas or liquid filled therein to escape.